# Radius of circle given area Calculator

## Calculates the radius, diameter and circumference of a circle given the area.

 area S 6digit10digit14digit18digit22digit26digit30digit34digit38digit42digit46digit50digit radius r diameter R circumference L
 $\normal Circle\\\vspace{5}(1)\ radius:\hspace{45} r=\sqrt{\large\frac{S}{\pi}}\\(2)\ diameter:\hspace{40} R=2r\\(3)\ circumference:\ L=2\pi r=\pi R\\$

 [1-10] /11 Disp-Num5103050100200
[1]  2019/02/10 11:39   Male / 60 years old level or over / An office worker / A public employee / A little /
Purpose of use
Wanted to find radius in metres of a circle which is 1 hectare in area. But this calculator doesn't understand units of area like hectare or acre.
[2]  2018/10/26 11:41   - / 50 years old level / Others / Very /
Purpose of use
pool calc
[3]  2018/09/15 14:59   Female / 50 years old level / Self-employed people / Useful /
Purpose of use
Have recipe for 3 X 21 cm meringue circles, want to make 4 smaller ones using same quantity of mixture so needed to know diameter of smaller circles!
[4]  2018/03/21 17:05   Male / 20 years old level / An engineer / Useful /
Purpose of use
Too lazy to do the calculation myself, simulating a perceived area of another geometric shape into what the given circular radii would be.
[5]  2017/11/14 08:35   Male / 20 years old level / An engineer / Very /
Purpose of use
Subwoofer cone area (Effective piston Area) was given in subwoofer specifications, but not cone diameter. Needed exact cone diameter.
[6]  2017/10/11 20:34   Male / 20 years old level / An engineer / Very /
Purpose of use
Video game development software.
Modulating virtual foliage density. Given a constant number of desired instances per surface area, I increase the surface area based on a foliage desire factor [0-1], where 1.0 keeps the current surface area, and 0.5 doubles it. If the desired number does not exceed the number of existing pieces of foliage in the area around the proposed foliage we do not place it.
[7]  2017/09/14 11:22   Male / 20 years old level / High-school/ University/ Grad student / Very /
Purpose of use
For normal measurement
Bug report
[8]  2017/09/08 11:16   Male / 20 years old level / Others / Very /
Purpose of use
Calculate varying radius of circular vents I need to CAD out with a given fixed area total.
[9]  2017/07/22 15:22   Male / 40 years old level / High-school/ University/ Grad student / Very /
Purpose of use
Geocaching
[10]  2016/09/09 03:08   Male / 60 years old level or over / A retired people / Useful /
Purpose of use
Exploring
Bug report
Great web site. However, your legend says:
(2) area: R=2r
this should be 'diameter:'
from Keisan
Thank you for pointing it out.

Sending completion

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